Question 1
An aluminum metal is a good conductor and is used for overhead cables. State any two other properties that make Aluminum suitable for this use
Answer
- Cheap
- Ductile
- Ductile
Question 2
Some Sodium chloride was found to be contaminated with Copper (II) oxide. Describe how a sample of Sodium chloride can be separated from the mixture.
Answer
– Add water to the mixture
- Sodium chloride dissolves where’s copper (ii) oxide is insoluble
- Filter to obtain sodium chloride as the filtrate and leave it to cool so as to obtain sodium chloride crystals
- Sodium chloride dissolves where’s copper (ii) oxide is insoluble
- Filter to obtain sodium chloride as the filtrate and leave it to cool so as to obtain sodium chloride crystals
Question 3
Study the flow chart below and answer the questions that follow
-
Name
(i) The reagent used in step (I)
(ii) Compound A. - Write an ionic equation for the reaction in step (iv).
Answer
-
(i) Dilute nitric acid (HNO3)
(ii) Lead (II) Sulphate (PbSO4) - Pb(OH)2(s) + OH-(aq) → P (Pb(OH)4)2-(aq)
Question 4
Study the information below and answer the questions that follow.
Explain why the ionic radius of
- K+ is greater than that of N+.
- Mg+ is smaller than that of N+
Answer
- K+ has more energy levels (three) than Na+, also ionic radius increases down the group. Greater shielding effect in K+ than Na+
- Both have two energy levels but effective nuclear charge is greater in Mg2+ than Na+ since Mg2+ has +2 charge where’s Na+ has +1 charge.
Question 5
5. Sulphur (IV) oxide and Nitrogen (IV) oxide react as shown in the equation below SO2 (g) + NO2 (g) → SO3 (g) + NO (g)
- Using oxidation numbers of either sulphur or Nitrogen show that this is a redox reaction.
- Identify the reducing agent
Answer
-
- SO2(g)